1. ORGANIC CHEMISTRY || Pharmaceutical chemistry department
Pharmacy college
Princess Nora University

2. Phenols

3. objectives Write the functional groups of phenols
differentiate between phenol and alcohols
Determine chemical and physical properties of phenol
Perform chemical and specific tests for phenols

4. Introduction
class of chemical compounds consisting of a hydroxyl group (—OH) bonded directly to an aromatic hydrocarbon group
Hydroxy benzene = phenol

5. What is the different between phenols and alcohols ?
Alcohol has an -OH group bonded to a sp3 carbon
phenols has an -OH group directly attached to a carbon of the aromatic ring (benzene).
AR-OH

6. Properties phenols are polar due to the ability to form hydrogen bond
phenols are water soluble
Phenol can dissolve in NaoH
Phenols are more acidic than alcohols but less acidic than Carboxylic acids.

7. Uses & toxicity Early uses for phenol was as an antiseptic.
Phenol is used as a starting material to make plastics, explosives such as picric acid.
Used in the production of aspirin and other pharmaceuticals.
Detergents and emulsifiers, and also in insecticide and plastics production
Phenols are hazard (handled with extreme caution).
Phenol is highly corrosive to the skin .
phenol will produce flammable vapors (highly toxic) .

8. Phenols
Phenol Resorcinol Catechol

9. Physical properties Phenol Resorcinol Catechol State
Solid ,crystalline
Solid, flaky
Solid, fine powered
Color
White
Buff
Gray
Odor
Phenolic odor or characteristic
Flammability
Flammable with luminous smoky flam
Effect on L.P
No change
Solubility
Soluble in water

10. Azo – dye formation test
Chemical test
General test
FeCL3
Azo – dye formation test
Specific test
Phthalein test

11. General test FeCL3 test :
Few mg of Phenols dissolve in water drop of FeCL colored triaryloxy complex
Results:
Phenol = violet color
Resorcinol = violet color
Catechol = Green color

12. General test FeCL3 test Results: Phenol Resorcinol Catechol
violet color violet color Green color

13. GENERAL TEST Azo – dye formation test (( Diazotization test))
1-2 dropof aniline (red color) + dil.HCl (until dissolve) + NaNO2 (sod. Nitrite solution) = until faint pale yellow color - PUT IN ICE
Few phenol + 10% NaOH (until phenol dissolved)
Add (1) on (2) gradually

14. GENERAL TEST
Result :
Phenol = ((Azo – dye formation))Orange – red color or ppt
Resorcinol = ((Azo – dye formation))Orange – red color or ppt
Catechol = No azo – dye form {Decomposition, dark purple color}
-naphthol
resorcinol
phenol
The dye is
Benzene azo -naphthol
Benzene azo resorcinol
Benzene azo phenol

15. GENERAL TEST Azo – dye formation test (( Diazotization test))
Phenol Resorcinol Catechol
No azo – dye form
{Decomposition, dark purple color}
((Azo – dye formation))Orange – red color or ppt

16. SPESIFIC TEST Phthalein test :
Few mg of Phenol + phatalic anhydride + 4 drops con.H2SO cool = then pour it in beaker contain 20 ml of 10%NaOH

17. SPESIFIC TEST Phenol = Pink color
Resorcinol = Green fluorescence added water = fluorescence
Catechol = Blue color

18. THANK YOU ..